The present invention relates to a shock absorber or shock absorbing apparatus (or system) including one or more shock absorbers for a vehicle.
A Japanese patent document JP H05(1993)-180259 shows a shock absorber capable of adjusting a damping force. This shock absorber is provided with a damping valve used in common for extension and compression. This shock absorber includes an extension side check valve on an upper chamber's side of a piston; a compression side check valve provided in a base valve; a communicating chamber between an inner shell and a cylinder formed with communication hole communicating with a lower chamber; and a reservoir chamber formed between the inner shell and an outer shell. The damping valve includes a valve element disposed between a primary pressure chamber communicating with the communicating chamber and a secondary pressure chamber, a pair of relief valves on the upper and lower sides of the valve element, and a poppet valve to vary a seat force.